What is the clinical manifestation of humoral hypercalcemia in canines with lymphoma?

Humoral hypercalcemia of malignancy, which can occur in dogs with lymphoma, typically results from the secretion of parathyroid hormone-related peptide (PTHrP) by neoplastic cells. This leads to increased calcium levels in the bloodstream, which can manifest as clinical signs related to hypercalcemia.

Excessive thirst and urination, known as polyuria and polydipsia, are common manifestations because elevated calcium levels can affect the kidneys’ ability to concentrate urine. This results in more dilute urine being produced, prompting increased thirst as the animal tries to compensate for fluid loss.

While depressed behavior and increased appetite can also occur in dogs with lymphoma, they are not direct results of hypercalcemia. Severe skin infections are unrelated since they do not tie into the normal effects of elevated calcium levels in the context of malignancy. Recognizing the signs associated with humoral hypercalcemia is crucial for the diagnosis and management of affected canines.